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3 Amps Battery Charger.Utility Circuit 2 — 31 Dec 2012

3 Amps Battery Charger.Utility Circuit 2


Here is a general purpose battery charger that can deliver 3 Ampere current at 12 Volts to charge Lead Acid battery or Tubular battery. The Ampere meter provided in the circuit indicates how much current is flowing into the battery. Two LED indicators are included to show the charging status.

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How to maintain Maintenance Free Battery? Tech Focus 5 — 28 Aug 2012

How to maintain Maintenance Free Battery? Tech Focus 5


“My UPS is not giving sufficient back up”. This is the most common complaint raised by PC users. It is not the fault of the UPS, but is due to the poor maintenance of its battery. Sealed batteries are used in UPS, Emergency lamps etc do not require water and acid top up. There is no water loss in these batteries during the charge/discharge cycle and it can be positioned in any direction like vertical, horizontal etc. These sealed batteries are known as SMF (Sealed Maintenance Free) or VRLA (Valve Regulated Lead Acid) batteries and they work on the oxygen recombination principle. SMF battery is totally maintenance free and has longer cyclic life, thus compensating the initial higher cost. One of the important aspects of battery life in relation to the use of equipment is the cut off voltage set in the equipment. If properly maintained, the sealed battery can give sufficient back up time. Let us see the tips to increase the life of UPS and Inverter battery.
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Battery Guard — 6 Aug 2011

Battery Guard


One of the major problems in Battery operated devices such as Emergency Lamp is the deep discharge of battery when the load operates for long time. If the Lamp remains on for long time, battery voltage reduces drastically and destroys the fluorescent lamp .The blackening of the ends of fluorescent tube is due to the  heating up of filament in low voltage. Deep discharge also reduces the battery life. As a rule 80% current should be present in the battery for normal battery charge / discharge cycles. This add on circuit is meant for battery protection which  never permits the battery to go below 4.5 V / 10.5 V and automatically shut off the emergency lamp.

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3 Amps Battery Charger — 16 Apr 2011
Tubular Battery Maintenance — 18 Apr 2010

Tubular Battery Maintenance


Battery maintenance is very important when we use Home inverters. Generally Tubular batteries are recommended due to its high efficiency and life span. Various makes and types are of batteries are available in the market. . Tubular batteries are recommended to backup UPS and Inverters where environmental conditions are tough and ambient temperatures are common. These are capable of long hours of backup and the life period is around five years.

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